JPS5893606A - Motorcycle - Google Patents

Abstract

PURPOSE:To improve the running stability, vibration and comfortable riding at the turning by installing the rear wheel with a radial tire having the specific structure. CONSTITUTION:The toroid shaped carcass 2 of a radial tire 1 is composed of the cord using the organic fibers having the reinforced layers more than at least one layer which is located at the angle of 70-90 deg. for circumferential direction central plane of the tire. The both end 3 of the said carcass 3 are folded back around a pair of the bead core 4 located on the extended location higher than the normal LT through the tread end TE. The cord at the crown part of the carcass 2 is arranged at the comparatively acute angle for circumferential central plane of the tire. The belt reinforced layer 5 is placed at the upper side of the both end 3 and arranged to be overlapping with the both end 3 of the carcass 2. Further, the reinforced rubber layer 6 which is externded from the one bead part to the other bead part through the tread part is interposed in the space surrounded by the carcass 2 and folded back part.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a cross-ply tire commonly used for motorcycles on the front wheel and a radial tire with a specific structure FiL on the rear wheel. Regarding motorcycles with improved stability, handling stability, vibration, and riding comfort.

Motorcycles are required to have good performance characteristics such as running stability, handling stability, and ride comfort when rolling, but these performance characteristics are said to be largely influenced by the tire structure, and therefore the structure of the tire itself has traditionally been Research has been conducted to improve this from a design perspective.
However, the inventor has discovered that in motorcycle tires, the functions are divided between the front wheel and the rear wheel, and the characteristics vary greatly depending on the combination of the structures of the tires mounted on the front and rear wheels. For example, in terms of steering stability, it is best to increase the cornering power and lateral rigidity of the front tires compared to the rear tires in order to prevent wobble mode (low-speed shimmy) occurring from the front wheels, and also to increase the cornering power and lateral rigidity of the front tires compared to the rear tires. It was found that lowering the cornering power of the #i rear wheels was effective for (high-speed silver #).

For this purpose, it is best to install a radial tire or semi-radial tire on the rear wheel, but in conventional radial or semi-radial tires, the carcass is approximately 90 degrees or close to 90'4 to the center plane in the circumferential direction of the tire. They are arranged at an angle, and therefore have too little lateral rigidity, and are inferior to camber thrust, which is the reaction force that restores the tilt of the vehicle body.

Conventional motorcycle tires employ a cross-ply structure, that is, a structure in which the cords of each adjacent layer intersect with each other at an angle of about 25 to 45 degrees with respect to the tire circumferential center plane, resulting in improved lateral rigidity. is excessive and does not meet the above requirements. Therefore, as a result of various studies on improving the required characteristics unique to such two-wheeled vehicles, the inventors decided to make the folded end of the carcass extend above the position corresponding to the tread end, and to interpose reinforcing rubber between the end and the carcass. We have found that the camper thrust can be optimized by this method, and that a motorcycle equipped with a radial tire of this structure on the rear wheel and a conventional cross-ply tire on the front wheel has excellent thin frame properties.

An object of the present invention is to provide a two-wheeled vehicle with excellent running stability, handling stability, and riding comfort when rolling, and one embodiment thereof will be described below based on the drawings. Fig. i11 is a cross-sectional view of the radial tire f1+ used for the rear wheel of the motorcycle of the present invention installed on the rim.

In the figure, a toroidal carcass T21 of a radial tire (1) is constructed by using a cord made of I/i organic fibers and at least one reinforcing layer arranged at an angle of 70 to 90' with respect to the tire circumferential center plane. and both ends (3
) is a normal line (L
T). Further, the crack part VcII'i of the toroidal carcass (2) is arranged such that the cord is inclined at a relatively shallow angle with respect to the center plane in the circumferential direction of the tire. Both 4 +31 upper −NC to polymerize with
A belt reinforcing layer (6) is arranged. flifMKI surrounded by the carcass (2) and its folded part in a rainbow/
i A reinforcing rubber layer (6) is interposed that extends from one ped part through the tread part to the other ped part.

! The organic fiber cord used for the 4fl carcass (2) is:
The cord is made of nylon, aromatic polyamide, polyester, rayon, etc., and aromatic polyamide fiber cord having an elastic modulus of 200 ypd or more is particularly preferably employed. In addition, the carcass can be formed in two or more layers in addition to the single ply. In this case, both ends (3) of the folded portion of at least one ply extend upward by a distance equivalent to the tread edge, and the folded portion of the other ply It is also preferable to position both ends of the ply near the flanges of the folded portion of the inner ply.

The cords of the belt reinforcing layer +il are arranged at a relatively shallow angle to the center plane in the circumferential direction of the tire, that is, 4G' or less, preferably at an angle of 10° to 30°, to improve the tread surface's ambidextrous properties, thereby improving straight running. Driving stability is further improved.

For the cord of the belt reinforcing layer +6), in addition to aromatic vocods such as nylon, polyester, rayon, and aromatic lyamide, inorganic fibers such as steel cords and glass fibers can also be used.

Next, the reinforcing rubber layer 1@l#iJ I SA hardness 65~
95° Preferably j-t The rubber in the range of 70' to 9G' is extended from the bead part to at least a position corresponding to the tread end to increase the lateral rigidity from the bead part to a part of the shoulder, but the reinforcing rubber layer mFi 1 As shown in the figure, by uniformly distributing the stiffness from one bead part to the other bead part, the stiffness is uniform throughout the tire. Hold.

It is preferable to make the lateral rigidity of 1 more uniform by configuring the reinforcing rubber layer (6) to have substantially the same thickness from the bead portion to the position corresponding to the tread end.

However, the radial tire (1) with the above structure has a carcass (
2) and relatively hard reinforcing rubber layers (6) are provided in the darkness at both ends (3) of the folded part that extends to the position equivalent to the tread edge, so the volume effect is greater than when both ends of the folded part IML are located low. This allows the side parts to be reinforced more effectively. As a result, while retaining the tire wear resistance and low fuel consumption inherent to radial tires, the K4 Yumper Thrust, which has been considered a drawback of radial tires, can be effectively improved.

Next, FIG. 2 shows a sectional view of a state in which a cross-ply tire (U) is mounted on the rim of the front wheel of a motorcycle according to the present invention. Carcass Jfi of cross ply tie-yul) in figure
It consists of at least two plies of cords made of organic fibers arranged at an angle of 20 to 60 degrees with respect to the center plane in the circumferential direction of the tire. It is folded back and terminates at U near the rim 2 flange. The plies are arranged so that the cords intersect with each other, forming a so-called cross ply. Tires with such a structure have strong lateral rigidity (traditionally, they have been used exclusively in motorcycle tires) has been adopted.

The motorcycle of the present invention is characterized in that the radial tire or semi-radial tire described above is used for the rear wheel, and the cross-ply tire is used for the front wheel. is installed on the rear wheel to improve high-speed vibration, and the front wheel is equipped with cross-ply tires that have high lateral rigidity and high cornering power, which improves low-speed shimmy and improves steering stability at high and low speeds. It can be greatly improved.

Furthermore, it is possible to maintain low wear resistance and fuel efficiency, which are characteristics unique to radial tires.

Example l.

Tire size 130/90 manufactured according to the specifications shown in Table 1
The lateral rigidity and wear resistance of V-18 tires were measured and shown in Table 111!1. In addition, a motorcycle with a tire on the front wheel and tire B on the rear wheel (Example 1), a motorcycle with tire A on the front wheel and tire C on the rear wheel (Example 2), and a motorcycle with tire A on the front wheel and tire C on the rear wheel (Example 2); Actual vehicle running tests were conducted on two-wheeled motorcycles (relatively large) equipped with the following. The results are shown in Table 2.

[Brief explanation of drawings]

@Figure 1 is a cross-sectional view of a radial tire mounted on a rim, and Figure 2 is a cross-ply tire on a rim.Table 1 Note 1) Tire A is shown as a reference and its relative value is shown. The higher the value, the better. Table 2 Note 2) This was a feeling test using actual vehicle driving, and a 5-stage evaluation method was adopted. A sectional view of the installed state is shown. (1)... Radial tire, (2)... Toroidal carcass, 13)... Both ends, (4)... Bead core, (
6)... Bell) 11 strong layer, (6)... Reinforced rubber layer,
i11+...Cross ply tire, L12...Bead core. Patent Applicant Sumitomo Rubber Industries Co., Ltd. Agent Patent Attorney Tadashi Naemura Figure 1, Figure 2 Procedural Amendment (Method) l Indication of Term Showa...Year 轡 11 No. 1.1.63 2 Axis Akira of,
411 II Two-wheeled wheel; 3 God IT: Nasuto II (Relationship with 1 Axis scream discharge - person. 4. Agent () Number of inventions increased by supplement D) Description 14 (2) Description 1. Title of the invention Motorcycle 2. Claims (1) At least two ply layers in which organic fiber cords are arranged at an angle of 20 to 60 degrees with respect to the circumferential center of the tire. A cross-ply tire with a carcass in which the plies cross each other and both ends are folded back by a pair of peed cores is installed on the front wheel, while an organic fiber cord is installed at an angle of 70 to 90 degrees with respect to the center plane in the circumferential direction of the tire. A toroidal carcass consisting of at least one reinforcing layer arranged in the direction P and extending from a position corresponding to the tread end to the direction P, and a crack part of the carcass inclined at a relatively shallow angle with respect to the center plane in the inner circumferential direction of the tire. A radial tire is equipped on the rear wheel with a belt reinforcing layer made of fibers or fiber cords arranged as shown in FIG. A motorcycle that is characterized by: 3. Detailed Description of the Invention The present invention focuses on installing a cross-type tire, which is commonly used for motorcycles, on the front wheel and a radial tire having a specific configuration on the rear wheel. Related to motorcycles with improved running stability, handling stability, vibration, and riding comfort. Motorcycles require performance characteristics such as running stability, steering stability, and riding comfort when the legs are set, but these characteristics are said to be largely influenced by the tire structure, and therefore, conventionally, the structure of the tire itself is Research has been conducted to improve this from a design perspective.
However, the inventor believes that in motorcycle tires, the front and rear wheels have different functions, and the characteristics can vary greatly depending on the combination of the structures of the tires installed on the front and rear wheels.
I found out. For example, in terms of steering stability, it is good practice to increase the cornering power and lateral rigidity of the front tires compared to the rear tires in order to prevent the waltz mode (low-speed shimmy) that occurs from the front wheels. It has been found that reducing the cornering power of the rear wheels is effective against Queeg mode (high-speed vibration).
For this reason, it is better to install a radial tire or semi-radial tire on the rear wheel, but in conventional radial or semi-radial tires, the carcass is about 900 to 90' from the center plane in the circumferential direction of the tire. As a result, the lateral rigidity was too low, and it was inferior to the camper thrust, which is the reaction force that recovers the tilt of the vehicle body. Conventional motorcycle tires employ a cross-ply structure, that is, a structure in which the cords of each adjacent layer intersect with each other at an angle of about 25 to 45 degrees with respect to the tire circumferential center plane, resulting in improved lateral rigidity. is excessive and does not meet the above requirements. Therefore, as a result of various studies on improving the required characteristics unique to such two-wheeled vehicles, the inventor made the folded end of the carcass extend above the position corresponding to the train and do ends (2) and interposed reinforcing rubber between the end and the carcass. It has been found that camber thrust can be optimized by doing this, and that a radial tire with this structure can be mounted on the rear wheel and a conventional cross-split tire can be mounted on the front wheel. The purpose of the present invention is to provide a two-wheeled vehicle with excellent running stability, handling stability, and ride comfort when cornering, and one embodiment thereof will be described below based on the drawings. I/I will explain. FIG. 1 shows a sectional view of a radial tire +11 used for the rear wheel of a motorcycle according to the present invention installed on a rim.
In the figure, the trochoidal carcass (2) of the radial tire 1.1) uses at least one reinforcing layer of cords made of organic weave arranged at an angle of 70° to 90° with respect to the center plane in the circumferential direction of the tire. The ends (3) are folded back around a pair of bead cores (4), and the normal line (LT) passing through the position corresponding to the tread end (TE)
) extends above. Further, the crack part of the toroidal carcass (2) has a cord so as to be inclined at a relatively shallow angle with respect to the center plane in the circumferential direction of the tire.
A belt reinforcing layer (
6) is located. Furthermore, a reinforcing rubber layer (6) is interposed in a region surrounded by the carcass (2) and its folded portion, extending from one ped part through the trend part to the other ped part. The organic fiber cord used for the carcass (2) is a cord made of nylon, aromatic polyamide, polyester, rayon, etc., but especially an aromatic polyamide fiber cord of 20%
A material having an elastic modulus of 0 fed or more is preferably employed. In addition, the carcass (2) can be formed not only in one ply but also in two or more layers, in which case both ends (31) of the folded part of at least one ply extend upward to a position corresponding to the tread edge, and the folded part of the other ply is extended above the folded part of the other ply. Both ends (3) of the folded portion of the inner ply, preferably, may be located near the rim flange.The cords of the belt reinforcing layer (6) are formed at a relatively shallow angle with respect to the center plane in the circumferential direction of the tire, that is, 40°. 'The straight running stability is further improved by arranging the belts preferably at an angle of 10° to 30° to increase the rigidity of the tread surface.The cords of the belt reinforcing layer (5) are made of nylon, polyester, rayon, In addition to aromatic vocords such as aromatic polyamide, inorganic fibers such as steel cords and glass 7-eyeper can also be used.Next, the reinforcing rubber layer (6) has a JISA hardness of 65 to 95 degrees.
Preferably, the reinforcing rubber layer (al is shown in FIG. As shown, uniformity of rigidity is maintained throughout the tire by integrally arranging it from one ped part to the other ped part.The reinforcing rubber layer (6) is made of approximately the same thickness from the ped part to the position corresponding to the tread edge. It is preferable to make the lateral rigidity of region B more uniform by configuring the radial tire fleI/i with the above structure, between the carcass (2) and both ends (3) of the folded portion extending to a position corresponding to the tread end. Since the relatively hard reinforcing rubber layer (6) is placed on the side N, the side N is reinforced more effectively due to the volume effect than when both ends (3) of the folded portion are located low. The camber thrust, which has been considered a drawback of radial tires, can be effectively improved while maintaining the tire wear resistance and low fuel consumption inherent to radial tires. The cross-sectional view with ply tires (11) installed is “-
show. In the final figure, the cross-ply tire (11) 7) The carcass (12) consists of at least two layers of cords made of organic fibers arranged at an angle of 20 to 60 degrees with respect to the center plane in the circumferential direction of the tire. (from the ply), its both ends OS are folded back around a pair of bead cores (i4) and terminate at ttm near the rim 2 range. The plies are arranged so that the cords intersect with each other, forming a so-called cross ply. Tires with such a structure have strong lateral rigidity (traditionally, they have been used exclusively for motorcycle tires). The motorcycle of the present invention is characterized in that the radial tire or semi-radial tire is used for the rear wheel, and the cross-ply tire is used for the front wheel, and the camper thrust and the lateral rigidity are combined to improve high-speed vibration. Furthermore, the front wheels are equipped with cross-ply tires that have high yokozuna performance and high cornering power, which improves low-speed shimmy and greatly improves steering stability at high and low speeds. Furthermore, it is possible to maintain low wear resistance and fuel efficiency, which are characteristics unique to radial tires. Example l. Tire size 180/90 manufactured according to the specifications shown in Table 1
The horizontal performance and abrasion resistance of V-18 tires were measured and shown in Table 1. In addition, an actual vehicle running test was conducted on a motorcycle (relatively large) with tire A installed on the front wheel and tire B installed on the rear wheel.Motorcycle A was installed on the front wheel and rear wheel. The results are shown in Table 2. Table 1 in the margin below indicates that the higher the rating, the better. Table 2 Note 2) This was a feeling test using actual vehicle driving, and a 5-level evaluation method was adopted. 4. Brief Description of the Drawings Fig. 1 shows a sectional view of a radial tire mounted on a rim, and Fig. 2 shows a sectional view of a cross-ply tire mounted on a rim. (1) Radial tire, (2) Toroidal carcass, (3) Both ends, (4) Beatcot, (5) Belt reinforcement layer, (6) ...Reinforced rubber layer -Eα→...Cross-sply tire, (14)
...Bead core. “ Patent applicant Sumitomo Rubber Industries, Ltd.

Claims (1)

[Claims] (1) The organic fiber cord is composed of at least two plies arranged at an angle of 20 to 6 G' with respect to the center of the tire in the circular direction, and the plies intersect with each other, and both ends thereof are formed by a pair of ped cores. A cross-ply tire with a folded carcass is mounted on the front wheel, while a tread consisting of at least one reinforcing layer of organic fiber cords arranged at an angle of 7 (1-90') to the tire circumferential center plane. a toroidal carcass extending upward from a position corresponding to the end; a belt reinforcing layer made of fiber cords arranged at a cracked part of the carcass so as to be inclined at a relatively shallow angle with respect to the center plane in the circumferential direction of the tire; The rear wheel KM is a radial tire equipped with a carcass and a reinforcing rubber layer extending from the bead to at least the vicinity of the tread edge in the dark part of the carcass.
A motorcycle characterized by: